Apparatus for supplying artificial pressure to oil sand



1928" J. o. LEWIS ET AL APPARATUS FOR SUPPLYING ARTIFICIAL PRESSURE T0 OIL SAND Filed Dec. 29, 1927 v 70 a} 46 70 3 W a; 'f. x 7

l I g0 73 32 3 /4 u l 5/ [I ;,/9 /0 r 8 2 I 39 A rr /7 25 I 2 5 y '36 INVENTORS James 0. Lew/5 ATTORNEY Patented Oct. 23, 192 8.

UNITED STATES JAMES O. LEWIS AND HOMER R. PIERCE, '01 TULSA, OKLAHOMA.

APPARATUS FOR S'lTPIIJYING ABTIFICIAL PRESSURE TO OIL SAND.

Application filed December 29, 1927. SeriaiNo. 243,312.

Our invention relates'to apparatus for supplying artificial pressure medium to Oll sand and more particularly to utilization of gases returned from producing wells of a group for re-circulation in such combination with added volume of atmospheric air as to avoid such co-mingling of the gases as to produce explosive mixtures.

' It is a common practice in fields where the natural rock pressure has become exhausted or depleted, to stimulate flow by supplying an artificial pressure medium, such as atmospheric air or natural gas, to one of-the wells in a group, commonly termed the air well, and through the sands to other wells of the group, commonly termed producing wells. This pressure medium, during its passage through the sand, becomes saturated with hydrocarbon content from the petroleum in the sand and may be employed as a fuel for operating or passed through condensers for the recovery of gasoline content.

It has also been a common practice to re circulate such artificial pressure medium through a compressor and back to the sand together with such added volume of atmospheric air as may be necessary for maintainmg a constant volume of circulating medium. Because of the hydrocarbon content of the returned medium, addition thereto-of atmospheric air produces an explosive mixture liable to ignition from backfire from the compressor engine or from other causes, but if the returned medium and atmospheric air are passed through the compressor and supply line withoutbeing co-mingled, danger of explosion is eliminated.

It is the principal object of our invention to alternately supply the returned gases and atmospheric air to the compressor so that they may be passed-through the supply line in a continuous stream but without co-mingling to form an explosive mixture, and in accomplishing this object we have provided means for automatically and alternately admitting the returned gases and fresh atmospheric air to the line leading to the comressor. so that all of the returned gases may e employed for-recirculation, together with the proper quantity of atmospheric air to compensate for losses and maintain a constant volume of supply to the airwell.

The preferred form of such apparatus is illustrated in the accompanying drawings,

wherein Fig. 1 is a diagrammatic view of a group of wells to which the air method of stimulatmg How has been applied showing a circulatmg system embodying our invention, some of the parts being exaggerated in size for better illustration.

Fig. 2 is an enlarged central section and perspective view of the automatic valve for controlling-admission of returned gases and atmospheric air to the line leading to the compressor.

1 Fig. 3 is an enlarged detail pers ective view of the control valve members an their operating mechanism.

Fig. 4 is a section onthe line 4-4 of Fig. 2.

Referring more in detail to the drawings:

1 designates the air well and 2 reducing wells of a group to which artificial pressure medium is to be applied for stimulating flow of liquid petroleum through the sand to the producing well by what is commonly known as the air method. 3 designates a compressor of multistage type, comprising the low pressure cylinder 4 and high pressure cylinder 5, the latter connected by a line 6 with the air well '-1 in accordance with ordinary practice, the compressor being preferably operated by an explosion engine 7.

Leading from the producing wells are branches 8 connected with pick-up lines 9 which connect with the main return line 10 through which pressure medium passed through the oil sand to theproducin wells may he returned to the compressor or recirculation.

Also leading from the producing wells are branches 8 which connect witha pick-up line 9 through which the fluid lifted from the wells is conveyed to storage tanks (not shown).

ll designates a' branch tapping the return line and leading to the engine 7 through which returned, saturated pressure medium may be delivered-to the engine for use as fuel, the branch being provided with a valve 12 for controlling flow therethrough. Intel-posed in the line 10 between the branch 11 and the compressor is a valve housing 13 comprising a receiving chamber 14 (Fig. 2) fed-through an intake channel 15 in communication with the supply end of the line 10, and communicating with thepart of the line 10 leading to the compressor and which for convenience will be designated 10', the chambers 14 and 16 being separated by a partition 18 having:

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a flat top portion 19 parallel with a flat bottom portion 20 on the body of the valve housing. The.parallel top and bottom members 19 and 20 are provided with ports 21 and 22 provided respectively with downwardly and upwardly facing valve seats 23 and 24. Surroundin the bottom port 22 andv preferably removaifiy attached to the valve housin is a skirt 25 comprising a chamber 26 and t roat 27 through which atmospheric air may be admitted to the outlet chamber 16 through the port 22. I 7

The wall of the inlet chamber 14 is extended and cupped at its upper end and provided with a shoulder 28 seating a cover plate 29 which may be attached to the "shoulder 28 H by screws or the like 30, and having a central aperture 31 registering with the valve ports -21 and 22 and rovided with a packing gland 32 of any suita 1e construction. Mounted on the top of the cupped extension 33 is a cap 34 co-operating with the body part of said extension to form the diaphragm chamber 35, the extension and cap members having out turned edge flanges 36 and 37 secured together by the bolts 38. Extending across the dia hragm chamber and clamped between the anges 36 and 37 by the bolt 38 is a flexible diaphragm 39 having a central aperture 40 registering with the valve ports 21 and'22 and protected on its upper and lower faces bywashers 41 and 42. The cap 34 has a central' aperture 44 also registering with the valve ports 21 and 22 and provided with a packing gland 45 of any suitable construction. Attached tothe top of the cap 34 pref- "erably by bolts 46 is a cage 47 having a central aperture 48 constituting aguideway for a valve stem. .The stem, 49, extends through the cage 47, through the packing gland 1n the cap 34, through the diaphragm 39,

through the packing gland 32 and through I the ports 21 and 22 into the skirt 25, being slidable in the cage and packing glands but fixed tothepdiaphra preferably by welding, '-as*indicated by t e spots 50, to the wash- *ers 40,a'n d 41 on the upper and lower faces of the diaphragm.

The stem carries valves 51 and 52 which are preferably adjustable thereon by lock nuts 54 threaded onto the stem and engaging the upper and lower surfaces of the valve members, the valve 51 being located above the top 19 of the partition 18 in order that it may seat downwardly to close the port 21 and the valve 52 being located below the valve port 22 so that it may move upwardly to close its port, the valves being so adjusted on the stem that: when one of the valves is seated to shut 0a flow through its p0rt,'the other valvewill be unseated to permit flow through the port which it controls.

The valve stem 49 extends above the cige 47 I and is pivotally connected with a track 54 by means of a pin or bolt 55 which extends with ears 57 on the cage 47 and with cars 58 dependin from'the track body in slightly s aced re ation to the ears 55 withwhich t e valve stem is connected. The track '54 comprises an initially horizontal body portion 59 provided with a bottom slot 60', a trap 61'fitting within the channel of the-track ing a stop for a rollm weight presently mentioned, and is adapte for ad'ustable location within the track by means 0 the bolt 63 and a set screw 64 adjustable by look nuts 65.

At its inner end the trap member is provided with a flexible lip 66 which is engaged by the end of the'set screw 64 to adjust it to various elevations and determine at what an- .gle of the trap the rolling weight is released from the trap; the rolling weight preferably comprising a roller 67 adapted to ride on the flanges of the track'member and having end flanges ,68 lying along the sides of the track rail to serve as keepers and guide the roller and has a curved upturned end 62 constitutduring its shiftin travel. The track member j 54 is bent u ward y at about the point of connection of t e valve stem and has an upturned end arm 69 serving as a stop for the rolling 4 scri body part in the horizontal position illustrated in Fig. 2 by scale weights 70 removably mounted on a link 71 suspended from an eye weight under the conditions presently deed. The track is normally held with its,

72 on the bolt 63, the weights being remov-j able from the link so that any number may be applied thereto according to the resistance it is desired to apply to opening movement of the valve in the return line.

Leading from the return 'line 10 to the diaphragm chamber 35 is a conduit 73 where by returned pressure medium may pass to.-

the lower portion of the diaphragm chamber and maintain a pressure therein equal to the I pressure in the return line.

Assuming the-parts to be constructed and assembled as described, the operation is as follows When the system is first put in operation,

atmospheric air is taken into the compressorand delivered through the. supply line to the air. well, from which it passes into the sand, forcingliquid petroleum in the sand to, the producing well, and finally escaping. from the producing well to the return-line 10. During passage of the pressure medium through the sand, it is enriched by hydrocarbon content of petroleum'in the sand so that a part ofthe return flow may be passed throng the engine supply pi e for combustion in the engine operating t 1e compressor. The balance of the returned pressure medium is delivered into the receiving chamber of the 1,ese,eee

control valve housing where it is trapped because of the closure of the valve ort 21 through the valve mechanism hereto ore deof the pressure medium through the conduit 73. When sufficient pressure medium has accumulated in the diaghrapm' chamber, the diaphragm is forced upwardly, lifting the valve stem to shut off the supply of atmospheric air through the port 22 and opening the port 21 to the receiving chamber 14 so that the enriched pressure medium may enter the compressor. When the valve stem is raised, the track 54 is rocked on its fulcrum until the track assumes an angle at which therolling weight will be displaced over the stop 66. When the roller is displaced it travels down the track onto the anglin arm 60, accelerating movement of the trac after it passes the apex of the angle, sd that the valves are given a snap opening and closing movement, thereby avoiding any extended period during which both the valves are open to simultaneously admit atmospheric air and returned pressure medium to the compressor line.

During the time the valve 51 is open, the enriched pressure medium flows into the compressor but as the air valve is closed during this period, there is no mixture of the two gaseous elements, the enriched medium following the fresh air and not co-mingling therewith to an extent which will produce a combustible mixture.

The enriched pressure medium continues to flow into the compressor until pressure has been reduced in the line, and the scale Weights 68 are again able to overcome the Wei ht of the roller 68. When the pressure has een reduced to a suflicient degree, the trap is rocked back to its normal position, sna ping the valves to close the port 21 and out o the supply of enriched pressure medium and opening the port 22 to again admit atmospheric air to the compressor. With this arrangement, admission of the enriched medium and atmospheric air alternates under automatic control of the valve mechanism so that alternate volumes of fresh air and returned medium pass through the supply line to the air well without co-mingling to form an explosive mixture.

What We claim and desire to secure by Letters Patent is: 1. In combination with a compressor, a line leading from the compressor forconducting fluid pressure medium to an air well, a line for returning fluid medium from a' producing well to the compressor, and means controlled by pressure in thereturn line for selectively admitting air or returned pressure medium to .the compressor. I a

2. In combination with a compressor, a'line leading from the compressor for conducting 7o fluid pressure medium to an'air well, a line for returnin fluid medium from a producing wellto t e compressor, separate valves controlling admission of air and returned fluid medium" to the compressor, and means con- '7 trolled by pressure of the returned medium for actuatin said valves.

3. In com ination with a compressor, a line leading from the compressor for conducting.

fluidpressure medium to an air well, a line for returnin fluid medium from a producing Well to the compressor, separate, oppositely operating valves controlling admission of air and returned fluid medium to the compressor,

and means controlled by pressure of the returned medium for actuatmgsaid valves.

4. In combination with a compressor, a line leading from the compressor for conducting fluid pressure medium to an air well, a line for returning fluid medium from a producing well to the compressor, a valve housing in the return line having separate valve ports for admission of air and passage of returned fluid medium, opposed valves controlling said ports, and means controlled by pressure in the return line for actuating said valves.

5. In combination with a-compressor, a line leading from the compressor for conducting fluid pressure medium to an air well, a line for returning fluid medium from a producing opposed'va ves controlling said ports, a diaphragm in the diaphragm chamber operatively connected with said valves, and connection between the dia hragm chamber and said return line, where y the diaphragm is subjected to variable pressures in the return line.

6. Apparatus of. the character described, comprising a compressor, a supply line leadmg from the compressor, a return line to the.

compressor, a control valve housing in the return line comprising a receiving chamber, a dellvery cham er and a diaphragm chamber, the delivery chamber havmg port connection with atmosphere and with the receiving chamber, 0p osed valves controlling sai ports, a diap ragm in the diaphragm cham-- ber connected with said valves, and means communicating the diaphragm chamber with the return line.

7. Apparatus of the character described,

com IlSlIl a compressor, a supply line leading rom t 1e compressor, a return line to the compressor, a control valve housing in the return line comprising a receiving chamber, a delivery chamber and a diaphragm chamthe diaphragm chamber with the return line.

8. Apparatus of the' character described, comprism a compressor,'a supply line leading from t e compressor,- a return line to the compressor, a control valve housing in the a delivery chamber and a diaphragm chamber, the delivery chamber having port connection with atmosphere and with the receivort's, a diaphragm in the diaphragm chamer, a stem connected with said valves and 4 with the diaphragm, means connecting the diaphragmchamber with the return line, a fulcrumed track connected with the valve stem, and a roller on said track for accelerating pivotal movement of the track to effect snap closure of the valves.

9. Apparatus of the character described,

comprisin a compressor, a supply line leadmg. from c compressor, a return line to the compressor, a control valve housing in the re-' turn line COIIIPIlSlIlg a receiving chamber, a

chamber, op'osed valves controlling said ports, a diap ragm in the diaphragm cham-'- bar, a stem connectedwithsaid valves and return line comprising a receiving chamber,

with the diaphragm, means connecting the diaphragm chamber with the return line, a

fulcrumed track connected with the valve ,--stem, having stop arms at its opposite ends, a ing chamber, opposed valves controlling said i stop member ad]ustable on said track, and a arms and stop member, substantially as set In testimony whereof we aflixour signatures. I

JAMES o. LEWIS. HOMER R. PIERCE.

40 roller on said track engageable with thestop 

